Be careful crossing water with a modified blue fan clutch and new fan (1 Viewer)

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landcruising

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I finally got my cooling temps down after installing a modified blue fan clutch. My journey Started 2 years ago with a radiator, new unmodified blue clutch, and thermostat, then a new fan, belts and modified blue clutch from wits end last month. Initially tried to modify the two year old blue clutch but the Phillip head broke off when removing, either way it was way out of spec from what others posted for operating temps. So decided to get one from wits end with all the cooling hoses. Ran great and cool in the Southern California desert until crossing deep water. The new fan must have had too much resistance and was pulled into the radiator catastrophically. This did not happen to 5 other 80's in the group. The fan may have also contributed since it was a bit more flexible than the old one, which was yellow and brittle when removed, I could break it with a bit a force. The new and old fans seemed identical in castings size etc. but the new one was not a Toyota but made by Aisin. I'm not sure what contributed more the modified blue fan clutch or the Aisin fan. Lesson learned, a new fan and modified fan clutch cannot move water, water wins.

fzj80 water 2.png
 
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Water is a lot harder to move than air.
 
What was your engine speed in relation to the other vehicles? That could also have an effect.
 
I had a good bow wake until I heard the noise of the fan, roughly during this picture, not sure of the speed. Slowed down after the noise. One 80 actually flew through and one stalled at the end of the crossing. I also believe 1 starter needed some persuasion to get restarted at the next stop. Out of a group of 18 Toyotas, (4runners, fj cruisers, gx460, 80's, 200 and 60 series) all with various lifts and tires driving at different speeds and gears and 2 with actually water over the hood, mine was the only one with the problem and the only one with a modified clutch I believe. I'm still checking other sources like motor mounts etc. to see if it could be something else. but given how inflexible the other fans were this leads me to believe that the stiff clutch and flexible fan is the culpret. I was also taller than half the vehicles on a 21/2 inch lift and 315s. Some were stock with just 33 inch tires.

fzj80 water 3.png
 
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Thats why people like going through water crossings backwards or manually keep the fan from spinning going forwards.

Water+fans=bad.
If you’re doing it a lot you might even want to remove the fan belt.
 
Thats why people like going through water crossings backwards or manually keep the fan from spinning going forwards.

Water+fans=bad.
I don’t like going through water crossings backwards. They’re scary enough going forwards.

:lol:
 
This is interesting to me since I just put in a new radiator with a blue fan clutch that I modified. So far, I'm loving it but it is cold out and so not a real test. What oil did you use?
 
One of guys in the group, mentioned that some guys that cross a lot of water., cut the shroud in half, add rivets to the bottom with fabed up plates, bolts on top to make removing the shroud and fan easier, just 8 bolts, like 5 minutes. Seems like work at first, but easier than loosening that dam alternator bolt one click at a time.
 
Post a pic of the gored side of the radiator
Just got home from the 4 day trip, the old one is still strapped to the roof rack in bag. I'll try to get a pict tomorrow. But basically it got pulled into the very bottom when it hit the water.
 
You can also put a tarp across the front end to prevent water intrusion and create a better bow wake. They actually make 4x4 bras for this purpose.
Screenshot_20191112-223703.png
 
I also have a modified clutch, changed out the fluid on a stock clutch. Same day, 3in lift 32.7in tires.

On a side note had a good time leading the tow rig to camp in the dark.

i-QxtX5Sj-X3.jpg


20191108_173613.jpg
 
Just got home from the 4 day trip, the old one is still strapped to the roof rack in bag. I'll try to get a pict tomorrow. But basically it got pulled into the very bottom when it hit the water.
That makes sense. I had the same issue with my SC fan clutch. The problem was two fold

the radiator was positioned slightly rearward and the blades would hit a curved section of the shroud and get pulled into the bottom of the radiator.

the solution was to move the radiator forward and remove some of that area in the fan shroud.

subsequently I realized tha Toyota changed the shape of that area in the fan shroud and I wondered why. Looks like it could be from radiator failures with water crossings
 
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Not seating the fan shroud properly can also lead to the fan being pulling into the bottom of radiator.
 

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